#include "LiquidCrystal.h"

#include <stdio.h>
#include <ysizet.h>
#include <string.h>
#include <inttypes.h>
#include "core.h"

// When the display powers up, it is configured as follows:
//
// 1. Display clear
// 2. Function set:
//    DL = 1; 8-bit interface data
//    N = 0; 1-line display
//    F = 0; 5x8 dot character font
// 3. Display on/off control:
//    D = 0; Display off
//    C = 0; Cursor off
//    B = 0; Blinking off
// 4. Entry mode set:
//    I/D = 1; Increment by 1
//    S = 0; No shift
//
// Note, however, that resetting the Arduino doesn't reset the LCD, so we
// can't assume that its in that state when a sketch starts (and the
// LiquidCrystal constructor is called).

LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
                             uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
                             uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
{
    init(0, rs, rw, enable, d0, d1, d2, d3, d4, d5, d6, d7);
}

LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t enable,
                             uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
                             uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
{
    init(0, rs, 255, enable, d0, d1, d2, d3, d4, d5, d6, d7);
}

LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
                             uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3)
{
    init(1, rs, rw, enable, d0, d1, d2, d3, 0, 0, 0, 0);
}

LiquidCrystal::LiquidCrystal(uint8_t rs,  uint8_t enable,
                             uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3)
{
    init(1, rs, 255, enable, d0, d1, d2, d3, 0, 0, 0, 0);
}

void LiquidCrystal::init(uint8_t fourbitmode, uint8_t rs, uint8_t rw, uint8_t enable,
                         uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
                         uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
{
    _rs_pin = rs;
    _rw_pin = rw;
    _enable_pin = enable;

    _data_pins[0] = d0;
    _data_pins[1] = d1;
    _data_pins[2] = d2;
    _data_pins[3] = d3;
    _data_pins[4] = d4;
    _data_pins[5] = d5;
    _data_pins[6] = d6;
    _data_pins[7] = d7;

    pinMode(_rs_pin, OUTPUT);

    // we can save 1 pin by not using RW. Indicate by passing 255 instead of pin#
    if(_rw_pin != 255)
    {
        pinMode(_rw_pin, OUTPUT);
    }

    pinMode(_enable_pin, OUTPUT);

    if(fourbitmode)
        _displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS;
    else
        _displayfunction = LCD_8BITMODE | LCD_1LINE | LCD_5x8DOTS;

    begin(16, 1);
}

void LiquidCrystal::begin(uint8_t cols, uint8_t lines, uint8_t dotsize)
{
    if(lines > 1)
    {
        _displayfunction |= LCD_2LINE;
    }

    _numlines = lines;
    _currline = 0;

    // for some 1 line displays you can select a 10 pixel high font
    if((dotsize != 0) && (lines == 1))
    {
        _displayfunction |= LCD_5x10DOTS;
    }

    // SEE PAGE 45/46 FOR INITIALIZATION SPECIFICATION!
    // according to datasheet, we need at least 40ms after power rises above 2.7V
    // before sending commands. Arduino can turn on way befer 4.5V so we'll wait 50
    //delayMicroseconds(50000);
    delay(50);
    // Now we pull both RS and R/W low to begin commands
    digitalWrite(_rs_pin, LOW);
    digitalWrite(_enable_pin, LOW);

    if(_rw_pin != 255)
    {
        digitalWrite(_rw_pin, LOW);
    }

    //put the LCD into 4 bit or 8 bit mode
    if(!(_displayfunction & LCD_8BITMODE))
    {
        // this is according to the hitachi HD44780 datasheet
        // figure 24, pg 46

        // we start in 8bit mode, try to set 4 bit mode
        write4bits(0x03);
        //delayMicroseconds(4500); // wait min 4.1ms
        delay(5);

        // second try
        write4bits(0x03);
        //delayMicroseconds(4500); // wait min 4.1ms
        delay(5);

        // third go!
        write4bits(0x03);
        //delayMicroseconds(150);
        delay(1);

        // finally, set to 4-bit interface
        write4bits(0x02);
    }
    else
    {
        // this is according to the hitachi HD44780 datasheet
        // page 45 figure 23

        // Send function set command sequence
        command(LCD_FUNCTIONSET | _displayfunction);
        //delayMicroseconds(4500);  // wait more than 4.1ms
        delay(5);

        // second try
        command(LCD_FUNCTIONSET | _displayfunction);
        //delayMicroseconds(150);
        delay(1);

        // third go
        command(LCD_FUNCTIONSET | _displayfunction);
    }

    // finally, set # lines, font size, etc.
    command(LCD_FUNCTIONSET | _displayfunction);

    // turn the display on with no cursor or blinking default
    _displaycontrol = LCD_DISPLAYON | LCD_CURSOROFF | LCD_BLINKOFF;
    display();

    // clear it off
    clear();

    // Initialize to default text direction (for romance languages)
    _displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;
    // set the entry mode
    command(LCD_ENTRYMODESET | _displaymode);

}

/********** high level commands, for the user! */
void LiquidCrystal::clear()
{
    command(LCD_CLEARDISPLAY);  // clear display, set cursor position to zero
    //delayMicroseconds(2000);  // this command takes a long time!
    delay(2);
}

void LiquidCrystal::home()
{
    command(LCD_RETURNHOME);  // set cursor position to zero
    //delayMicroseconds(2000);  // this command takes a long time!
    delay(2);
}

void LiquidCrystal::setCursor(uint8_t col, uint8_t row)
{
    int row_offsets[] = { 0x00, 0x40, 0x14, 0x54 };

    if(row >= _numlines)
    {
        row = _numlines - 1;  // we count rows starting w/0
    }

    command(LCD_SETDDRAMADDR | (col + row_offsets[row]));
}

// Turn the display on/off (quickly)
void LiquidCrystal::noDisplay()
{
    _displaycontrol &= ~LCD_DISPLAYON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}
void LiquidCrystal::display()
{
    _displaycontrol |= LCD_DISPLAYON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// Turns the underline cursor on/off
void LiquidCrystal::noCursor()
{
    _displaycontrol &= ~LCD_CURSORON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}
void LiquidCrystal::cursor()
{
    _displaycontrol |= LCD_CURSORON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// Turn on and off the blinking cursor
void LiquidCrystal::noBlink()
{
    _displaycontrol &= ~LCD_BLINKON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}
void LiquidCrystal::blink()
{
    _displaycontrol |= LCD_BLINKON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// These commands scroll the display without changing the RAM
void LiquidCrystal::scrollDisplayLeft(void)
{
    command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVELEFT);
}
void LiquidCrystal::scrollDisplayRight(void)
{
    command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVERIGHT);
}

// This is for text that flows Left to Right
void LiquidCrystal::leftToRight(void)
{
    _displaymode |= LCD_ENTRYLEFT;
    command(LCD_ENTRYMODESET | _displaymode);
}

// This is for text that flows Right to Left
void LiquidCrystal::rightToLeft(void)
{
    _displaymode &= ~LCD_ENTRYLEFT;
    command(LCD_ENTRYMODESET | _displaymode);
}

// This will 'right justify' text from the cursor
void LiquidCrystal::autoscroll(void)
{
    _displaymode |= LCD_ENTRYSHIFTINCREMENT;
    command(LCD_ENTRYMODESET | _displaymode);
}

// This will 'left justify' text from the cursor
void LiquidCrystal::noAutoscroll(void)
{
    _displaymode &= ~LCD_ENTRYSHIFTINCREMENT;
    command(LCD_ENTRYMODESET | _displaymode);
}

// Allows us to fill the first 8 CGRAM locations
// with custom characters
void LiquidCrystal::createChar(uint8_t location, uint8_t charmap[])
{
    location &= 0x7; // we only have 8 locations 0-7
    command(LCD_SETCGRAMADDR | (location << 3));

    for(int i = 0; i < 8; i++)
    {
        write(charmap[i]);
    }
}

/*********** mid level commands, for sending data/cmds */

inline void LiquidCrystal::command(uint8_t value)
{
    send(value, LOW);
}

inline unsigned int LiquidCrystal::write(uint8_t value)
{
    send(value, HIGH);
    return 1; // assume sucess
}

/************ low level data pushing commands **********/

// write either command or data, with automatic 4/8-bit selection
void LiquidCrystal::send(uint8_t value, uint8_t mode)
{
    digitalWrite(_rs_pin, mode);

    // if there is a RW pin indicated, set it low to Write
    if(_rw_pin != 255)
    {
        digitalWrite(_rw_pin, LOW);
    }

    if(_displayfunction & LCD_8BITMODE)
    {
        write8bits(value);
    }
    else
    {
        write4bits(value >> 4);
        write4bits(value);
    }
}

void LiquidCrystal::pulseEnable(void)
{
    digitalWrite(_enable_pin, LOW);
    //delayMicroseconds(1);
    __no_operation();
    digitalWrite(_enable_pin, HIGH);
    //delayMicroseconds(1);    // enable pulse must be >450ns
    __no_operation();
    digitalWrite(_enable_pin, LOW);
    //delayMicroseconds(100);   // commands need > 37us to settle
    delay(1);
}

void LiquidCrystal::write4bits(uint8_t value)
{
    for(int i = 0; i < 4; i++)
    {
        pinMode(_data_pins[i], OUTPUT);
        digitalWrite(_data_pins[i], (value >> i) & 0x01);
    }

    pulseEnable();
}

void LiquidCrystal::write8bits(uint8_t value)
{
    for(int i = 0; i < 8; i++)
    {
        pinMode(_data_pins[i], OUTPUT);
        digitalWrite(_data_pins[i], (value >> i) & 0x01);
    }

    pulseEnable();
}
